John h



(N0 Model.)

J. H; EIGKERSHOFFN COMPOUND STEAM ENGINE.

No. 459,507. Patented Sept. 15,1891;

' fizl'fwr. M1 26: 1 gh lliefimlgyt 111: mm; menu cu menu-mm, wunmufou, n. c.

UNITED STATES PATENT OFFICE.

JOHN H. EIOKERSHOFF, OF CINCINNATI, OHIO, ASSIGNOR TO THE TRIUMPH Y COMPOUND ENGINE COMPANY, OF SAME PLACE.

COMPOUND STEAM-ENGINE.

SPECIFICATION forming part of Letters Patent No. 459,507, dated September 15, 1891.

Application filed October 3 1889. Serial No. 325,897- (No model.)

To a whom it may concern.-

Be it known that I, JOHN H. EIcKEEsHoEE, a citizen of the United States, residing at Oincinnati, Ohio, have invented new and useful Improvements in Compound Steam-Engines, of which the following is a specification.

My invention relates to compound steamengines, its object being to produce, in economical and compact form, a compounding engine in which the steam, after being utilized at boiler-pressure, is further expanded directly and without the intervention of a receiver against a piston of increased area.

To this end my invention consists in the engine constructed and arranged as hereinafter more fully set forth, embodying, as a leading constructive and operative principle, two steam-cylinderseach of two diameters in successive axial portions, a corresponding piston for each cylinder, consisting of a pis ton-head for the larger end of the cylinder extended at reduced diameter as an axial guide-plunger into the smaller end, a crankshaft having driving-cranks set at opposite radii and contained in a crank-case, pitman connections between the plunger-pistons and the cranks, respectively, and two independent distribution-valves moved by the shaft over suitable ports and having the triple function of governing the induction, eductlon, and transfer of steam in relation to the pistons.

Mechanism embodying my invention is illustrated in the accompanying drawings, in -which Figure 1 is a vertical section of a preferred form of my invention through the common axial plane of the cylinders, passing centrally through the valve-chests and valves, showing the crank-shaft connections and valve-moving mechanism in elevation; Fig. 2, a horizontal section through both cylinders and centrally through the valves on a reduced scale, Fig. 3, an under plan view of one of the duplicated valves on a reduced scale.

The general type of engines to which my invention is applied is that in ,WlllGll the cylinders are mounted (preferably) vertically above-and open into a crank-case, through which thecrank-shaft passes, having ournalbearings in the end walls, and in which the cranks operate.

Constructive details are not material to my present invention, excepting as to those features specifically described.

The two cylinders A B, Fig. 1., are provided with integral axial extensions A B, of reduced diameter, projected forward toward the crank-shaft and opening into the crankcase G below, to which they are bolted. Each cylinder with its fittings is a duplicate of the other and is closed above by a suitable head and provided with a piston D, extended by a close-fitting trunk or hollow plunger D of properly-reduced diameter into the axial extension of the cylinder. The cylinders and their axial extensions'being truly bored from a common center alignment and the pistons and their extensions being truly turned in like manner, each piston with its extensions practically constitutes a cross-head of extended longitudinal bearing for the pitman, which is pivoted within the plunger-piston and coupled to the crank F in the crankcase G below.

I provide one or more packing-rings upon each piston D, and also at the lower terminus of each extension, so that the pistons and their extensions may operate steam-tight in the cylinders and extensions, respectively. The crank-shaft H extends through the case Gin the common axial plane of the cylinders, having a bearing in the opposite end walls of the case, and is preferably provided with a bearing H within the case centrally between the cranks F. I

Each steam cylinder is provided with a valve-chest, a reciprocating slide-valve, and ports I) d, opening'through the shell of the cylinder to the interior thereof at or near the respective ends and directly through the valve-seat. An exhaust-port e opens through the seat beyond the cylinder-head into a common exhaust-passage c. The valve-chests communicate and maybe considered as a single valve-chest I, common to both cylinders, arranged between them, which brings the two valve-seats opposite and the slide-valves O 0 back to back. The valves are of the D variety, two-ported, having considerable lap, and a wide port 0 at one end and a narrow port 0 at the other, the ports being connected by a hollow bridge or conduit 0.

Steam enters the common valve-chest I at an aperture t, and surrounds the valve-conduit c and the valves, except their contact-faces, with the seats, so that the distribution of steam from the high-pressure to the low-pressure valves are driven simultaneously in opposite directions with the proper alternating mo-' tion by a single eccentric. I may also place on the back of one of the valves a springcushion n, bearing against the parallel face at the back of the opposite-valve to hold them properly to seats when steam is shut off, yet admit of yielding under excess of back pressure.

The general operation is as follows: Steam from the boiler enters at 2', filling the valvechest I. A port Z) being uncovered, steam enters the cylinder 13, for example, and expends its force against the annular space at the lower side of the piston D, around the extension D, and moves the iston 11 Ward, P

The valve C of said cylinder being moved downward first covers the port 19, and later,1

coincidently with the completion of the upward stroke of the piston D, opens the portv I) to the port a of the valve,and the latter, opens the opposite port 0 to the correspond ing port cl of the cylinder, whereby the ports band 01 are brought into communication through the conduit 0 of the valve, allowing the steam to pass'fromthe under side to the upper side of the piston D, and by difference'of areas the excess of pressure at the upper side drives the piston downward. It will be noted that the action of the steamin both strokes of the piston takes place atopposite sides of the same piston and within the same inclosing cylinder, thereby conserv-. ing all advantages of temperature. 'At the conclusion of the downstroke the port 0 of the valve spans the ports cl and e of the valve-. seat and exhausts the steam into the passage e. This action being repeated at opposite times by the opposite valve and cylinder, the motion is communicated.

proper driving through the pitman E to the cranks 'F and shaft H.

I claim as my invention and desire to secure by Letters Patent of the United States- 1. In a double-acting compound engine, the combination, substantially as set forth, of two cylinders, each bored out to a larger and smaller diameter in the upper and lower portions, respectively, of its length, a closed crank-case, into which said cylinders open side by side, constituting the base-support of the engine, a crank-shaft journaled in and through said crankcase below the cylinders and having oppositely-set cranks, trunk-pistons fitting said cylinders, pitmen connecting said pistons with the cranks, respectively, two distribution-valves operating upon seats open to a common steam-supply space, each governing the supply, expansion, and exhaustports of one of the cylinders, and a single valve moving in connection with the crankshaft, reciprocating both valves simultaneously in opposite directions, respectively, substantially as set forth;

2. In a double-acting compound engine, the combination of two cylinders bored out to a larger and smaller diameter in the upper and lower portions, respectively, of their length, trunk-pistons fitting said-cylinders, a crank shaft journaledin bearings below-the cylinders and provided with oppositely-set cranks, pitmen coupling said pistons and cranks, two valve-seats extended vertically beyond the cylinders,admission-ports leading from each seat into its cylinder adjacent to opposite ends of its larger bore, eXhaust-portsleading from the seats beyond the cylinders, and a pair of distribution-valves reciprocating upon the valve-seats in opposite directions, each governing independently the entire distributive functions of one of the cylinders, substantially as set-forth.

3. In adouble-acting compound engine, the combination of two cylinders, each'having a forward prolongation of reduced diameter and a corresponding trunk piston, a-supporting crank-case into whichthe cylinders open, a crank-shaft journaled in and through the crank-case below'the cylinders and provided with oppositely-set cranks, pitmen coupling said pistons and cranks, two valve-seats, each havingadmission-ports adjacent to opposite ends of the larger bore of its cylinder and exhaust-ports leading outward abovethe cylinders, and two elongated reciprocating distribution-valves operating upon the seats, respectively, each havingports and an internal connecting-passage carried wholly Within the valve for the expansion over of steam toopposite sides of the working-piston, substantially as set forth.

4. In a compound engine, the combination of two cylinders, each bored to a larger and smaller diameter in the upper and lower portions, respectively,of :its length, correspond ing trunk -pistons fitting said cylinders, a crank-shaft provided with oppositely-set cranks and journaled in bearings'below the cylinders, pitmen coupling thepistonsto the cranks, respectively, two valve-seats open to a common steam-supply space, a pair of distribution-valves operating upon the seats, respectively, each governing the entire distribution of one cylinder, a single eccentric upon the main shaft, and reversed connections for operating said valves simultaneously in opposite directions, respectively, substantially as set forth.

5. In avertical double-acting compound engine, the combination of two parallel working cylinders, each having a guide prolongation of reduced diameter, a crank-case upon which said guide-extensions rest, supporting said cylinders, a valve-chest for each cylinder -merged into one structure joining the cylinders, a valve for each cylinder effecting the entire distributive function independently as to each cylinder, a reciprocating piston in L. M. HOSEA, ELLA HOSEA. 

